Question

The sodium metal is represented by ‘Na'. Its atomic number is:

• A. 12
• B. 11
• C. 14
• D. 13

Hint:

Sodium has symbol \(Na\) and atomic number \(11\). Its electronic configuration is \(2,8,1\).

Answer 1

The Correct Option is B

Sodium is a chemical element. Its chemical symbol is: \[ Na. \] The symbol \(Na\) comes from the Latin name: \[ \text{Natrium}. \] Every element has an atomic number. Atomic number means the number of protons present in the nucleus of an atom. For sodium: \[ Z=11. \] This means a sodium atom has: \[ 11 \] protons. In a neutral sodium atom, the number of electrons is also: \[ 11. \] Its electronic configuration is: \[ 2,\ 8,\ 1. \] Because it has one electron in the outermost shell, sodium is highly reactive and belongs to alkali metals. Therefore, the atomic number of sodium is: \[ 11. \]